any force responsible for maintaining an object on a curved path around a fixed center. In introductory coursework this is usually "uniform circular motion" and yields several simple and useful relations. Not to be confused with the centrifugal pseudo-force experienced in a accelerated referenced ...
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4answers
123 views
Is it possible to whirl a point mass (attacted to a string) around in a horizontal circular motion *above* my hand?
I'm studying circular motion and centripetal force in college currently and there is a very simple question but confuses me (our teacher doesn't know how to explain either :/), so I hope we can sort ...
0
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0answers
46 views
What force does the seat exert on the rider at the top and bottom of the ride? [closed]
A 75 kg person rides a Ferris wheel which is rotating uniformly. The centripetal force acting on the person is 45 N. What force does the seat exert on the rider at the top and the bottom of the ride?
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1answer
63 views
Centripetal force and circular motion
I have a doubt, say when a body moves in a circular loop, there are basically two types of acceleration acting on the object. One is the linear acceleration which is basically tangent to the circle, ...
0
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1answer
66 views
Change in speed of a satellite
Suppose there's some satellite orbiting the earth in circular motion. Suppose there's an asteroid that hits the satellite in the same direction as the instant velocity vector of the satellite. The ...
-1
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1answer
87 views
Confusions about rotational dynamics and centripetal force
I am a high school student. I am having confusions about the centripetal force and rotational motion . I have known that a body will be in rest or in uniform velocity if any force is not applied. But ...
4
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0answers
136 views
Friction in circular motion [closed]
A circular horizontal table spins around its axis of rotation with a constant angular speed. It completes one revolution in 2 seconds. An object whose mass is $M = 0.8 \ \text{kg}$ is placed on the ...
4
votes
1answer
102 views
Effect of water on wobble of rotating structure
If we have a structure that rotates to create artificial gravity, then if the mass isn't perfectly distributed along the circumference the CM will be offset from the geometric center so there will be ...
9
votes
2answers
154 views
Can an orbit be calculated using two points and transit time?
Working in only two dimensions and assuming that the central body is at the origin of the coordinate system, given two points in space and knowing the transit time between those points, as well as the ...
0
votes
1answer
91 views
Rotating sphere and circular trajectory: minimum speed
I have a sphere (mass = 3 kg), constrained to a fixed length rope, rotating (radius = 5 m) on a vertical plane.
My textbook ask me about the minimum speed in the highest point in order to keep the ...
0
votes
1answer
226 views
Physics of Banked Curves at an angle [closed]
When calculating the normal force of an object on a ramp inclined at an angle,
the force of gravity is broken into components: $f_{gx}$ and $f_{gy}$, where $f_{gx} = f_g \sin (\theta)$ and $f_{gy} = ...
1
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2answers
128 views
Fictitious Forces $\overset{?}{⇔}$ Constraint Forces (re: D'Alembert's Principle)
Are fictitious forces and constraint forces the same thing?
0
votes
1answer
124 views
Vertical Loop like Anti-gravity
Let's take a bottle (no cap) with half its volume filled with water. If we rotate the bottle at some slower average velocity, water does not drop out of it. The same principle works on Roller ...
0
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1answer
196 views
Is my understanding of the mechanics of skidding correct?
I'm trying to understand the mechanics which determine if a car making a turn will skid.
Are the following correct or incorrect:
A vehicle making a turn will skid unless the centripetal force is ...
2
votes
1answer
189 views
When does centripetal force cause constant circular motion?
As far as I know, if an object has a speed $s$ and a force is applied to it which generates an acceleration of $s^2/r$, then the object will start moving in a circle of radius $r$. Also, as far as I ...
2
votes
1answer
350 views
Circular Motion Equation Derivation
I am given a series of three equations, which someone has used to determine the Tension force in a rope swing:
$$mgh=1/2mv^2$$
$$T-mg=\frac{mv^2}{r}$$
$$T=3mg=1764N$$
I am asked to exaplain the steps ...
0
votes
2answers
889 views
Circular motion period equation
The equation,
$$ a_c=\frac{4\pi^2r}{T^2} $$
Can be expressed as:
$$ F_c=\frac{m4\pi^2r}{T^2} $$
I am confused as to how to arrive at this second equation, and the relationship between these two ...
1
vote
2answers
119 views
Please explain this circular movement problem [closed]
I was working over some problems from my physics textbook, and I came across this one, it involves circular movement:
A car with the mass of 1t is moving over a hill with the velocity of 20 m/s. The ...
5
votes
5answers
552 views
Turning an Airplane. What actually causes the circular motion in a banked (roll) turn?
Basically I'm wondering if this is correct. Which essentially says that you need a torque to get the nose of the craft to turn and that this is provided by the rear tail surfaces.
After trying to ...
1
vote
3answers
642 views
Centripetal force of a rotating rigid body?
Consider someone pushing a roundabout in a playground. Initially the
roundabout is stationary, but when it is pushed, it rotates with
increasing rotational speed.
The force of the push is ...
0
votes
3answers
1k views
Centripetal/Gravitational Force
Suppose a satellite is orbiting the Earth. The gravitational and centripetal force supposedly point towards the Earth. Therefore, the net force is towards the Earth. Since the satellite doesn't fall ...
4
votes
4answers
626 views
Increasing mass' effect on the balance between centripetal force and centrifugal force
Okay, this is nothing more than a thought experiment which popped into my head while driving home from work today.
Take the case of a single body orbiting another, larger body, as in a planet and a ...
7
votes
3answers
462 views
Shape of rotating rope (lasso problem?)
Let's take a wire or a rope. I usually do this with a chain or my scarf.
I fixate one end in my hand and apply rotation (by subtle movements of this endpoint like spinning a lasso). The rope gets ...
2
votes
5answers
293 views
Find drag force on link of rotating chain
Given a closed chain with a total length of 1.2m rotating at 1'800 rpm and a total mass of 0.4kg, what is the drag force pulling on one chain link?
I originally thought that since no link size was ...
7
votes
2answers
804 views
Relativistic centripetal force
The thought randomly occurred to me that a circular particle accelerator would have to exert a lot of force in order to maintain the curvature of the trajectory. Many accelerators move particles at ...
2
votes
3answers
953 views
Why did they add a Centripetal Force in the Free-Body Diagram?
problem
!
solution
!
Why do they have the centripetal force in there? I understand that the normal force is the centripetal force here, but why would they say "or $\frac{mv^2}{r}$"? I thought it ...
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1answer
232 views
centrifugal force in static frame of reference
The other day we derived Kepler's third law.
$$
\left( \frac{T_1}{T_2} \right)^2 = \left( \frac{r_1}{r_2} \right) ^3
$$
In order to derive this, you can look at a given planet that revolves around ...
2
votes
4answers
341 views
why does what get pushed away when centripetal acceleration is towards the center
If centripetal acceleration is towards the center, then why - when you spin a bucket of water (a classic demonstration) - does the water not get pushed out but rather stays in the bucket without ...
